


The Favorite

by AnnieRya



Series: Bio! Parent AU's [4]
Category: Batman - All Media Types, Miraculous Ladybug
Genre: Bio! Dad au, Bruce doesn't even know about her, Gen, Maribat Bio Dad Bruce Wayne Month, Marinette Dupain-Cheng | Ladybug is a Wayne, Older sister Marinette, until Damian tells him
Language: English
Status: Completed
Published: 2020-09-24
Updated: 2020-09-24
Packaged: 2021-03-08 01:20:29
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,211
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26607373
Author URL: https://archiveofourown.org/users/AnnieRya/pseuds/AnnieRya
Summary: Damian used to try and kill his sister and she always escaped before they came but now Marinette needs help and he's dragging their family to Paris to help his favourite sibling.
Relationships: Marinette Dupain-Cheng | Ladybug & Damian Wayne
Series: Bio! Parent AU's [4]
Series URL: https://archiveofourown.org/series/1843807
Comments: 11
Kudos: 579





	The Favorite

**Author's Note:**

> I am looking for someone to write a small snip it for a bio dad Bruce Wayne only he doesn't know. The one whom does is Damian and the only reason everyone else finds out is something happens to Marinette and Damian is like we must go to Paris our sister is in need of our families help  
> ask on tumblr

Damian Wayne always knew about his half-sister, she was older than him and she used to be the ban of his existence before they somehow managed to bond.

The two had met when Damian was assigned to kill her “To clear up any future problems.” as his mother put it, and he thought it would be an easy mission but he was very wrong. Even though she hesitated to hurt him at first she, in no uncertain terms, beat his ass(even though Marinette was left limping with a couple fractured ribs)

His grandfather was impressed and sent him after her five more times to see if she was just lucky, and each time she left still breathing and pissed at her brother, his mother and grandfather had sent him the sixth time with a truce and he almost got shot in the head.

Damian managed to dodge the arrow, “I don’t suppose would be willing to talk this time?” He asked her.

Marinette kept the weapon aimed at him, ready to shoot when necessary, “I’m offering you the same courtesy you gave me Ah-gul.” She sneered at him.

“Where did you even get a compound bow?” He questioned her, “Did you get it behind your moms back because your aim speaks volumes about your lac-” She shot the assassin behind him in the leg him in the middle of his speech.

“Who’d be surprised what Nonna teaches me when my parents are away.” She yelled at him, “Now what do you want from me baby brother?” She added, wondering why he wasn’t trying to slit her throat yet

“A truce.” He responded,

Marinette thought about it for a bit, “Fine.” She accepted, “But with two conditions.” She added, he said anything within reason.

“One, you clean up the mess you all made.” Marinette stated, for a twelve-year-old she was intimidating, “And two you don’t come back to my home.” She finished.

“Add if I don’t honour these requests?” He inquired.

Marinette gestured to the bow, “I’m young, cute and the last person to be a suspect for the murder of a tourist found dead in the alley next to the bakery.” She deadpanned, if the cops asked waterworks and bluebell eyes made them feel bad about asking trying to ask.

The two came to an agreement and the moment Damian was gone post clean up(and a good 20 minutes of making sure he was really gone Marinette ran to the bathroom and puked.

“I’m never doing that again.” She groaned tossing the weapon to the side, murder wasn’t her thing but they sure weren’t gonna hear that from her.

The next morning after getting the best sleep in months she acted like everything was fine with her parents and put the bow in the closest.

Damian was unhappy that he failed to kill his sister but accepted she had earned her life.

0-0-0-0-0

He decided to contact his sister a few weeks after moving in with his father, at first she was tempted to throw her phone in the river but the two soon began to actually have a healthy family relationship, with Marinette listening to him complain about the stupidity that was their adoptive siblings.

He was happy to have his sister since she was the only ‘normal’ sibling he had and wasn’t stupid sometimes and Marinette was grateful to have someone to vent to about being Ladybug(figured out himself, sneaky son of a b*tch, literally)

Until one day she didn’t pick up, he wasn’t worried at first until one day became two and he called one of the numbers his sister gave him.

Alya Cesaire wasn’t pleased with having to deal with his attitude and refused to speak to him about what was going on(she didn’t trust him when it came to miraculous business an didn’t know he eas Mari’s brother) and it wasn’t until he spoke to Kagami he learned his sister had literally passed out from exhaustion and Paris could be in danger.

Damian was gonna have a talk with his father about this.

0-0-0-0-0

“Damian what made you call a meeting at 4am?” His father asked, his siblings had similar sentiments.

“Father something dire has been brought to my attention in regards Paris.” Damian stated seriously.

His father raised a brow at that, “Explain.” Bruce ordered.

He proceeded to tell them all that he knew about the Heroes, Hawkmoth and the Akumas, It sounded absurd at first but it was too detailed to be false, that and it came from Damian.

“Wait a minute, just how do you know all this?” Dick asked in the middle of his explanation.

Damián glared at him for the interruption, “I was informed by our sister who is in need of our help.” He stated.

All of his family were in silence for a few minutes before Jason decided to speak up.

“She had another demon spawn!” He yelled referring to Talia. 

“Marinette is my half-sister you idiot!” Damian shouted, He turned to his father.

“Sabine Cheng is her mother.” He informed him, His father got a far off look before facepalming.

After two hours of swearing, phone calls to an ex, booking a flight to Paris, a league meeting being scheduled and Stephine being thankful for another sister, the million-dollar question was asked by Gordon “How did you find out about Bruce's kid before him?”

“I tried kill her.” He reviled, all of the family stopped at stared at him.

“Well looks like I already have something in common with her.” Jason muttered.

His father looked concerned learning his daughter, who he hadn’t even met, had already been targeted by the league of assasins, “What do you mean by tried?” He inquired.

“I was tasked to kill her five times and she escaped every time.” Damian admitted, “This sixth time I offered a truce after she tried to shoot me with a bow.” He added, Jason snorted.

“Roy’s gonna like her.” he mumbled amused.

0-0-0-0-0-0

The trip to Paris was long but they evenly made it to the bakery, Damian went in first and immediately came face to face with his sister who he immediately hugged to the shock of all of everybody

“What the-” Marinette mumbled, “Did you people clone him?” She asked the Waynes in English.

He pulled back pulled away, “I’m relieved you didn’t get yourself killed Marinette, don’t expect another.” He grumbled, His sister looked at Bruce.

“So, your my biological father?” Marinette asked hesitantly.

“I am, and can confirm that I didn’t know about you until this week.” He stated not wanting her to think he abandoned her.

Marinette gave him a hug, “I know, I don’t think you would have a problem with having another child.” She said, gesturing to his arsenal of children.

After the family reunion(and Jason proclaiming she was the only sane hero in the family) Marinette was able to tell them more about Paris and Bruce was very angry when he learned that her team had previously requested assistance from the league only to be told to stop playing pranks.

Damian was happy his sister had help now and hopefully, he didn’t have to suffer having their crazy family alone anymore.

THE END

**Author's Note:**

> Kudoa, please  
> Comments, I'd love it.


End file.
